28249722 has 48 divisors (see below), whose sum is σ = 65231712. Its totient is φ = 9156240.

The previous prime is 28249721. The next prime is 28249723. The reversal of 28249722 is 22794282.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28249721) and next prime (28249723).

It is not an unprimeable number, because it can be changed into a prime (28249721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17197 + ... + 18767.

It is an arithmetic number, because the mean of its divisors is an integer number (1358994).

Almost surely, 2^28249722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28249722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32615856).

28249722 is an abundant number, since it is smaller than the sum of its proper divisors (36981990).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28249722 is a wasteful number, since it uses less digits than its factorization.

28249722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1625 (or 1613 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 28249722 is about 5315.0467542628. The cubic root of 28249722 is about 304.5589684141.

The spelling of 28249722 in words is "twenty-eight million, two hundred forty-nine thousand, seven hundred twenty-two".